Compounds of the anthrapyrimidine series



. aminoanthraquinone with formamide.

Patented May 19, 1936 'UNITED STATES PATENT OFFICE COMPOUNDS OF THE ANTHRAPYRIMIDINE SERIES Max Albert Kunz, Mannheim, and Karl Koeberle,

Ludwigshafen-on-the-Rhine, Germany,

sig'nors to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application August 11, 1932, Serial No. 628,441. Renewed December 10, 1935. In Germany January 21, 1931 4 Claims.

The present invention relates to new compounds of the anthrapyrimidine series.

It is already known that 4-amino-1,9-anthrapyrimidine may be produced by treating 1,4-di- 4-amino- 1,9-anthrap-yrimidine is a yellow crystalline powder which melts at 276 to 278 0., which is practically unvattable and has no affinity to the vegetable fibre.

We have now found that new valuable cornpounds of the anthrapyrimidine series are obtained by treating heteronuclear amidated anthraquinones in which at least one amino group is in the alpha-position with amides of monocarboxylic acids, especially formamide or by treating heteronuclear amino-alpha-acylaminoanthraquinones with ammonia; heteronuclear amidated anthraquinones are for example 1,6-, 1,7- and 1,8-diamino-anthraquinones and their derivatives. The resulting new compounds correspond to the general formula in which R, R1 and R2 stand for hydrogen, alkyl or aryl; they are readily vattable and some of them have the character of Vat dyestuffs; they are important intermediate products for the production of dyestuffs; furthermore they produce clear, very fast and powerful dyeings on acetate silk. The first of the abovementioned reactions may be carried out with the addition of organic diluents, as for example phenol and its homologues, and may be accelerated by the addition of catalysts, as for example boric acid or anhydrous oxalic acid. In many cases, for example when the alpha-amino group is only capable of being converted into the pyrimidine ring with difiiculty, it may be advantageous to use an excess of the acid amide; for example formamide, itself as a diluent. Instead of the amines, the corresponding heteronuclear mono or dialkyl or -ary1amino-alphaaminoanthraquinones may be employed. The acylamino-alpha-aminoanthraquinones of the said kind, when treated with formamide, yield the corresponding acyl derivatives of LQ-anthrapyrimidine from which the acyl groups are split off by saponification, if desired in one operation with the condensation.

If other acid amides than formamide are employed Py-C-substituted anthrapyrimidines are obtained, for example Py-C-methyl compounds in case acetamide is used. Further 'anthrapyrimidines of the kind in question being substituted in the Py-ring may be obtained by treating the corresponding anthrapyrimidones with agents capable of replacing oxygen or hydroxyl groups by halogen as for example phosphorus pentachloride. In the Py-C-halogenanthrap yrimidines thus obtained the halogen atom can readily be replaced by organic radicles either directly by condensation with amino or hydroxy compounds, or by way of the corresponding diazo compounds which may be obtained from the amines prepared from the halogen compounds by heating them- 1-amino-5-benzoylaminofi-benzoylaminod, 9- anthraquinone anthrapyiimidine and when this is saponified, 5-amino-1,9-anthra pyrimidine is obtained.

The anthra'p'yrimidines obtainable according to the present invention may contain any substituent connected to the Py-C-atom, in particular halogen, alkyl, aryl, aralkyl, amino, substituted amino, hydroxy, alkoxy, nitro and cyano groups. The aforesaid anthrapyrimidines substituted on the Py-C-atom by organic radicles may be produced by employing another acid amide than formamide, for example acetic amide, for the condensation with an alpha-aminoanthraquinone.

produce these substituted anthrapyrimidines from the corresponding anthraquinone-1(N),2- oxazoles'by heating them with ammonia under pressure. A further convenient method for producing these substituted anthrapyrimidines consists in starting from the corresponding anthrapyrimidones which may also contain a nitro, alkyl,

'alkoxy, aryloxy group or a halogen atom inthe anthraquinone nucleus, with agents capable of 7 replacing oxygen or hydroxy groups by halogen,

such as the halides of phosphorus or sulphur, for example phosphorus pentachloride, tribromide, trichloride, thionylfchlorideandthe like, or benzo trichloride, antimony pentachloride and arsenic .pentachloride. In the Py-C-halogenanheated to boiling while stirring in 75 parts of formamide and 100 parts of phenol until a sample withdrawn and worked up melts at about 250 C. The whole is then allowed to cool,.is diluted if necessary with methyl alcohol and the 5-amino-1,9-anthrapyrimidine formed is filtered off by suction. It is a brown red powder which dissolves in concentrated sulphuric acid giving a yellow orange coloratiomyields an orange vat and dyes cottontherefrom blue red shades. When crystallized from organic solvents of high boiling point, or deposited. from. concentrated sulphuric acid by, the. careful addition of water, it separates in the form ofrviolet to brown red small needles melting between 256 and 257 C. A

,The reaction may also be carried out in liquid carbolic' acid (mixture of phenol and its homologues) In order to shorten the duration of the reaction, small amounts of anhydrous oxalic acid oriboric anhydride may be added.' a i A' product having the same properties is obtained from 1-amino-5-benzoylaminoanthraquinone by treatment with formamide and heating the resulting 5- benzoylamino-1,9-anthrapyrimidine dissolved in concentrated sulphuric acid to 120 C. with the addition of an amount of water necessary to saponify the benzoyl group .(about of the amount of concentrated sul- V sion of 0.1 part of the 5-amino-1,9-anthrapyrimidine obtained as described above in 300 parts of water after the addition of about 1 part of soap. The silk is then rinsed, washed and dried in the usual manner and a red dyeing having very good fastness properties is obtained. From 5-methylamino-1,9-anthrapyrimidine a reddish violet dyeing is obtainable. 5-gamma-propanol- It is, however, more suitable to amino-1,9-anthrapyrimidine dyes acetate silk powerful Bordeaux red shades.

By the method described in the first paragraph of this example, 5-methylamino-1,9-arithrapyrimidine may be obtained from 'l-amino-S methylaminoanthraquinone, and a mixture of 5-amino- 4- and -5methoxy-1,9-anthrapyrimidine may be obtained from 1,5-diamino-4-methoxyanthra- Example 2 25 parts of 1,7-diaminoanthraquinone together With .100 parts of formamide are heated for several hours in 100 parts of boiling phenol; The mixture is then .cooled'to about C., diluted with 200 parts of ethyl alcohol and the reaction product filtered oil by suction. It is. a brown powder which crystallizes in the form of blue red needles and dissolves in concentrated sulphuric acid giving a green yellow coloration. It dyes acetate silk orange red shades and gives an orange alkaline vat from which cotton is dyed.

bluish red shades.

Example 3 parts of 1,5-diaminoanthraquinone are heated with parts of nitrobenzene, 50 parts of phenol, 200 parts of formamide and 10 parts of anhydrous cupric sulphate while stirring at to C. whereby the water formed during the reaction is distilled off. When a sample dissolved in sulphuric acid and precipitated by the addi- 7 tion of water separates in violet flocks the reaction mixture is allowed to ,cool and the solvents are distilled, off by means of steam. The solid residue is filtered off from the remaining mass by suction and dried. The reaction product obtained has the same properties as the reaction product described in Example 1. V

In order to purify the crude productlOO parts thereof are dissolved in,500, parts .of 96 per cent sulphuric acid. Water is. added until a concentration in sulphuric acid of 60 percent results. The mixture is allowed to coolfdown to 20 to 3010. and the undissolved matter is filtered ofi by suction and washed with 60 per cent sulphuric acid. 'Water is added to the filtrate andthe precipitate is filtered off by'suetion, washed until it is neutral anddried.

If the reaction 'is carried out in nitrobenzene' instead of amixture of nitrobenzene and phenol it is advantageous to add a further 100 parts .of formamide after 1 to 2 hours. 7

a Example 4 100' parts of 1,8-diaminoanthraqulnone are heated with 100 parts of nitrobenzene, 100 parts of phenol, 200 parts of formamide and 20 parts of boric aoidat 185 'to 190 C.'while stirring ..and distilling off the water formed in the reaction. If a sample dissolved insulphuric acid and precipitated by water separates in violet-blue flocks, the reaction mixture isallowed to cool and the crystalline 8-amino-1,9-anthrapyrimidine formed is filtered oil by suction. It forms violet-red needles, dissolves in concentrated sulphuric acid giving a golden yellow color and gives a brown vat.

Example 5 100 parts of l-amino-5-benzoylaminoanthraquinone are heated with 200 parts of formamide, 200 parts of phenol and 5 parts of ammonium vanadate for about 1 hours at 180 C. to 190 C. Then 200 parts of water are added and the reaction product is filtered oil by suction after cooling and washed with hot water to which advantageously a small quantity of caustic soda solution is added. The reaction product obtained in a nearly quantitative yield is 5-benzoylamino- 1,9-anthrapyrimidine. The reaction product is then saponified, for example in the manner described in Example 1.

Instead of ammonium vanadate other catalysts may be employed, for example sodium vanadate, ammonium molybdate, cupric chloride, metal oxides such as cupric oxide, vanadium trioxide and pentoxide and metals as for example copper.

Also if nitrobenzene is employed instead of phenol, 5-benzoylamino-1,9-anthrapyrimidine is obtained, the reaction period being 2 hours.

Example 6 parts of 1,7-diaminoanthraquinone are heated with parts of formamide, 100 parts of nitrobenzene and 5 parts of ammonium vanadate at C. to C. until the color of a sample dissolved in concentrated sulphuric acid does no longer change when formaldehyde is added. Then the reaction mixture is diluted at about 80 C. with 100 parts of alcohol. The reaction product is filtered off by suction and washed with alcohol and hot water; it is a brown crystalline powder. According to analysis and its properties the reaction product is 7-amino-1,9-anthrapyrimidine. After being recrystallized twice from trichlorobenzene its melting point is 278 to 281 C.; it dissolves in concentrated sulphuric acid giving a yellow color. If the sulphuric acid solution is diluted with water a violet sulphate is precipitated.

In a similarv manner 6-amino-1,9-anthrapyrimidine may be produced from 1,6-diaminoanthraquinone.

The present application is a continuation-inpart of our copending application Ser. No. 586,692, filed January 14, 1932.

What we claim is:

1. Readily vattable compounds of the aminoanthrapyrimidine series which contain an amino group in a nucleus which has no part in the building up of the pyrimidine ring and which correspond to the general formula in which R1 and R2 stand for hydrogen or alkyl.

2. 5-amino-LQ-anthrapyrimidine crystallizing from high boiling organic solvents in the form of small violet to brown red needles, melting between 256" and 257 C., dissolving in concentrated sulphuric acid giving a yellow orange coloration, yielding an orange vat from which cotton is dyed blue red shades and dyeing acetate silk red shades of very good fastness.

3. 7-amino-1,9-anthrapyrimidine crystallizing from trichlorobenzene in the form of blue red needles, melting at 278 to 281 0., dissolving in concentrated sulphuric acid giving a green yellow solution from which a violet sulphate may be precipitated by the addition of water, dyeing acetate silk orange red shades and giving an orange vat from which cotton is dyed bluish red shades.

4. 8-amino-1,9-anthrapyrimidine, crystallizing in violet red needles, dissolving in concentrated sulphuric acid giving a yellow to brown color dyeing cotton brown shades from a brown vat and dyeing acetate silk red shades.

MAX ALBERT KUNZ. KARL KOEBERLE. 

